Mild cognitive impairment in multiple system atrophy: a brain network disorder.

Area of Science:

• Neuroscience
• Neurology
• Neurodegenerative Disorders

Background:

• Cognitive impairment (CI) is increasingly recognized in multiple system atrophy (MSA), a neurodegenerative disorder.
• Mild cognitive impairment (MCI) affects up to 44% of MSA patients, impacting executive functions, attention, visuospatial, and verbal abilities.
• The pathophysiological mechanisms of CI in MSA remain controversial despite evolving understanding.

Purpose of the Study:

• To review current understanding of cognitive impairment in multiple system atrophy.
• To explore potential structural and functional brain changes associated with MCI in MSA.
• To highlight the need for further research into MSA's cognitive decline.

Main Methods:

• Review of recent neuroimaging studies (morphometric and functional analyses).
• Analysis of findings related to gray matter volume and functional connectivity.
• Discussion of neuropathological findings in moderate to severe CI and limitations in MCI stage.

Main Results:

• Neuroimaging studies show conflicting results regarding gray matter atrophy.
• Functional analyses indicate reduced connectivity in specific brain regions (parietal lobe, cuneus, precuneus, limbic structures, cerebello-cerebral circuit).
• Structural and functional changes in subcortical limbic structures and cerebello-cerebral networks may link to early cognitive decline in MSA.

Conclusions:

• Early cognitive decline in MSA may involve subcortical limbic structures and disrupted cerebello-cerebral networks.
• Moderate to severe CI in MSA often involves co-pathologies like Alzheimer's and Lewy body disease.
• Further neuroimaging and neuropathological studies are crucial for understanding MCI in MSA, developing biomarkers, and enabling early diagnosis and treatment.